java基于web3j 玩转eth

1.查询ETH钱包余额:
private static final String URL = “http://127.0.0.1:8545/”;
Web3j web3 = Web3j.build(new HttpService(URL));
EthGetBalance ethGetBalance = null;
try {
// 通过账户地址查询余额
ethGetBalance = web3j
.ethGetBalance(“0xac***f0261bc4b0*0d5e23d9f80d24bf89fe”, DefaultBlockParameterName.LATEST)
.sendAsync()
.get();
} catch (Exception e) {
throw new Exception(“查询钱包余额失败”);
}
1eth = 10e18 wei
单位转换:
BigDecimal banlance = Convert.fromWei(ethGetBalance.getBalance().toString(), Convert.Unit.ETHER);

2. 通过钱包密码和助记词找回私钥公钥
   通过密码与助记词获得钱包地址、公钥及私钥信息
   Credentials credentials = WalletUtils.loadBip39Credentials(walletPwd, memorizingWords);
   //公钥16进制字符串表示
   String publicKey = credentials.getEcKeyPair().getPublicKey().toString(16);
   //私钥16进制字符串表示
   String privateKey = credentials.getEcKeyPair().getPrivateKey().toString(16);

3.获得当前区块高度
Web3j web3j = EthUtil.getConnection();
Request request = web3j.ethBlockNumber();

4.解锁账户，发送交易前需要对账户进行解锁
/**
* 通过http连接到geth节点
*
* @return
*/
private static HttpService getService() {
return new HttpService(URL);
}
public static Admin initAdmin() {
return Admin.build(getService());
}
Admin admin = EthUtil.initAdmin();
Request request = admin.personalUnlockAccount(address, password, duration);
PersonalUnlockAccount account = request.send();

5.查询区块内容
Web3j web3j = EthUtil.getConnection();
DefaultBlockParameter defaultBlockParameter = new DefaultBlockParameterNumber(blockNumber);
Request request = web3j.ethGetBlockByNumber(defaultBlockParameter, true);
EthBlock ethBlock = request.send();